GB-A-846,468 (Columbia Southern Chemical Corp.) describes a beneficiation process in which ilmenite is heated with sodium hydroxide. The mixture forms two phases; a liquid, titanium rich phase and a solid, titanium poor phase. The phases are separated while hot and the alkali leached away to leave a titanium enriched residue.
A problem with the prior art process is that it is difficult to manipulate the hot phases. Moreover, the caustic consumption is very high, which makes the process unattractive commercially.